var util = require('util');

function Base() {
    this.name = 'base';
    this.base = 1991;

    this.sayHello = function () { 
        console.log('Hello ' + this.name);
    };
}

Base.prototype.showName = function () { 
    console.log(this.name);
};

function Sub() {
    this.name = 'sub';
}

util.inherits(Sub, Base);

var objBase = new Base(); 
objBase.showName(); 
objBase.sayHello(); 
console.log(objBase); 
var objSub = new Sub(); 
objSub.showName(); 
//objSub.sayHello();    //error, sayHello未被继承
console.log(objSub); 